Nasal/ˈneɪzl/ Definition 1 of 4Pro Tip 1/2Health Matters When 'nasal' describes medical conditions or treatments, it involves the nose's health. She developed a nasal blockage that made it hard to breathe. Pro Tip 2/2Physical Anatomy 'Nasal' can refer to any structure related to the nose, like the nasal cavity. During the anatomy class, we learned about the nasal passages.